!0

On Thu, Feb 12, 2009 at 02:34:37PM +0000, Dirk Koopman wrote:
> Just been studying a CPAN module and I see a load of references to !0.
> Er, what is that? Googling most unhelpful.
It must be the prefix factorial operator.
$ perl -E 'say !0'
1
$
and 1 is 0 factorial. qed.
Abigail